The economy of each of China’s first-tier cities — Beijing, Shanghai, Guangzhou and Shenzhen — is now bigger than Singapore’s, according to revised figures.

Many Chinese cities have released gross domestic product numbers for 2016 using a revised methodology set down in July by the State Council, the country’s cabinet. The new system counts research and development outlays as fixed capital rather than intermediate input, thus helping to boost the GDP figures.

Singapore’s GDP was USD296 billion last year. China’s new way of calculating economic size bumped up Shenzhen’s by CNY59 billion to CNY2 trillion (USD302 billion), making it the third city to top that mark after Shanghai and Beijing. Guangzhou’s 2016 GDP added about CNY26 billion to hit almost CNY2 trillion.

Shanghai was the first mainland Chinese city to surpass Singapore’s GDP in 2009. Beijing overtook the city-state in 2013.

The size of Guangzhou and Shenzhen’s economies derives from large numbers of migrant laborers. Their populations are 2.5 and 2.15 times that of Singapore, so their per-capita GDP is not even half that of the south-east Asian state.

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